Head Balloons Inc AX7 77B N30721 accident near Chatsworth, Illinois

Probable cause

The balloon’s encounter with unexpected wind gusts during inflation, which resulted in the balloon becoming prematurely airborne and subsequently the pilot being ejected from the basket and one passenger receiving serious injuries while attempting to egress from the pilotless balloon.

NTSB analysis

The commercial pilot reported that, while inflating the balloon with hot air in light wind, he heard people yelling and stopped burning; he turned and saw another balloon that was airborne and swinging around. The accident balloon then became airborne and started swinging around very rapidly. He looked down and realized that spectators on the ground were directly below his balloon, and he immediately started burning to add heat so that the balloon would rise and not descend on spectators. Due to concern for spectator safety, the pilot felt his only recourse was to attempt to climb the balloon to avoid injuring the spectators on the ground. However, the accident balloon did not rise and instead struck the ground twice, and the pilot was ejected from the basket. Due to the decreased weight after the pilot was ejected, the balloon rose and flew off with two passengers still in the basket and subsequently landed about 2 blocks away. The passengers jumped out, causing the balloon to rise again. The balloon descended a final time about 1/4 mile away in a field.

A review of weather reports from a nearby airport revealed that the wind was 5 knots. A spectator on the ground provided videos of the balloons before and during the accident sequence. The spectator reported and the videos showed that the wind was calm, followed by gusts. Based on the available evidence, it is likely the accident resulted from unexpected wind gusts that led the balloon to prematurely become airborne.

Text from the NTSB. Open the NTSB docket for CEN17LA223 for the full record.